Three people were killed and 15 others injured in an explosion inside a four-storey building in Pakistan's southern port city of Karachi on Wednesday morning, local media said.
The explosion happened on the first floor of the building located in Gulshan-e-Iqbal area of the city, and the powerful blast also damaged the ground floor, Dawn News reported.
The killed and injured people included residents and workers of a private bank located on the ground floor of the building. Several vehicles and motorbikes parked outside the building were also destroyed in the blast, the report added.
Shortly after the blast, local police issued a statement saying that the blast happened due to the explosion of a gas cylinder inside the building, but it was later withdrawn after rescue and investigation teams found traces of explosive materials from the debris of the building.
A bomb disposal squad also reached the site to determine the exact cause of the explosion. Meanwhile the rescue operation is underway in the area.
The injured people have been shifted to a nearby hospital where seven of them are said to be in critical condition.
No group or person has claimed the attack yet.
